Made approx. 1852, this is as fine a double as I've ever seen. The quality of this rifle is such that I believe it cannot be improved upon. Barrels are 31 15/16" long with bores that measure .490"x .535" and in very good condition.
After playing with this rifle for awhile, I've come to the conclusion that the double rifle had been perfected by this time, maybe even earlier with only technical advances occurring.
There is no standing rear sight as part of the usual set up but for the short range stuff you simply use the notch in the standing breech. Due to the fit of this rifle, its all you need.